Brush 2 large baking dishes with vegetable oil. Pat the wings dry. Spread them between 2 sheets so they bake evenly until golden, 40 to 45 minutes.

As the chicken cooks, whisk together the dijon mustard, honey, mustard powder and celery seeds in a bowl. Remove the wings from the oven and toss with the mustard mixture, then continue baking until glazed, 5 to 6 more minutes and serve!